Azotobacter vinelandii aldehyde dehydrogenase regulated by sigma(54): role in alcohol catabolism and encystment.

ABSTRACT: Encystment in Azotobacter vinelandii is induced by n-butanol or beta-hydroxybutyrate (BHB). We identified a gene, encoding an aldehyde dehydrogenase, that was named aldA. An aldA mutation impaired bacterial growth on n-butanol, ethanol, or hexanol as the sole carbon source. Expression of aldA increased in cells shifted from sucrose to n-butanol and was shown to be dependent on the alternative sigma(54) factor. A mutation in rpoN encoding the sigma(54) factor also impaired growth on alcohols. Encystment on n-butanol, but not on BHB, was impaired in aldA or rpoN mutants, indicating that n-butanol is not an inducer of encystment by itself but must be catabolized in order to induce encystment.

SUBMITTER: Gama-Castro S 

PROVIDER: S-EPMC100092 | biostudies-literature | 2001 Nov

REPOSITORIES: biostudies-literature